1961 Benelli 50cc Racing Bike

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This 1961 Benelli is believed to be one of four factory bikes constructed for the 1962 50cc World Championship and the Isle of Man TT race. Power is provided by a 50cc 2-stroke single mated to a 4-speed transmission. Unfortunately the bikes were eventually to prove uncompetitive in racing, and this example passed through the hands of several prominent collectors before being purchased by the seller six years ago. It was featured on BaT in early 2012, and the seller has used it primarily for display purposes. This Benelli racer is now being offered on a bill of sale out of Indianapolis, Indiana. The Benelli 50cc race bikes featured specially-constructed frames but used stock moped forks and wheels. The steering head was sourced from Campagnolo bicycle parts, and fiberglass fairings were added. The early race history is unknown, but this example shows paint chips and stress cracks in the fairings consistent with competition use. The windscreen is broken, but the seller can provide the missing piece. Clip-on handle bars are equipped, and shifting is accomplished by a moped-style left hand twist grip. No instrumentation is provided, and stock triple clamp retains the perch for handlebars. The fuel tank is reported to be the original steel item. The 50cc 2-stroke single was capable of 10,000 rpm and is linked to a 4-speed transmission. Performance modifications consist of improved porting, megaphone exhaust, and a larger Dell’Orto UA 17 S carburetor with velocity stack. Cooling slots have been cut in the magneto cover. Gearing is for the track with a 27-tooth rear sprocket and a 13-tooth front sprocket, which gives it a 9.09 to 1 ratio good for speeds up to 75 mph. The unusual 2.25 rear tire is the same as fitted to the race bikes in period, and the megaphone exhaust is reported to add power as well as decibels.